Safety control for presses



Nov. 12, 1935. I L M KAHN 2,020,839

SAFETY CONTROL FOR PRESSES Filed Sept. 29, 1931 54C Cf 11V VEN 7 'ORPatented Nov. 12, 1 935 UNITED STATES,

PATENT OFFICE 5 Claims.

This invention relates to improvements in pressing machines for variouspurposes whose operation may involve danger to the operator. It can beused in any power press, but is more particularly related to garment andlaundry presses, on which the moving head of a press must be controlledin such a manner as to positively protect the operator against anyhazardous actions on her part.

Among the objects of this invention is provision of a simple mechanicaldevice whereby the operator is forced to employ both of her hands forthe control of the movable head-of such laundry presses. Another objectis to provide for the actuation of the machine by foot means, which isreleasable by hand operated means. These are other objects of myinvention are attained in the construction hereinafter set forth andclaimed.

Reference is had to the accompanying drawing in which like numerals andcharacters refer to corresponding parts throughout the different views.

Figs. 1 and 2 are respective frontand side elevations of a laundrypress. Fig. 3 is an enlarged top view of part of the safety controldevice. Figs. 4 and 5 are respective front and side views of amodification of a certain element of the safety control device.

My invention is here shown applied to a conventional type of laundrypressing machine consisting of a frame ID, a stationary buck H, amovable head l2, operated by a toggle joint mechanism l3, which isactuated by a pressure cylinder l4, connected with lever l5 to saidmechanism l3.

The cylinder is operated through two valves or main control members l6and ll of which the former is employed to release an air pressure whichwill cause the piston in said cylinder to press head I 2 against buckll.

Valve I1 is employed to release an air pressure to cause a reversemotion of said piston and head l2.

Both valves are fed by a source of power through pipe l9, having thereina stopcock 29 to cut off the power.

A bar fastened to the front part of frame It has fulcrumed to both itsends two operating levers 2| and 22. Fastened to their extremes arerespective cords or chains 23, 24 passing over respective pulleys 25 and26 held 'to frame l0. Cords 23 and 24 are fastened to respectiveslidable rods 21, 28 located on respective bearing blocks 3i, 32 securedto frame H). To each slide rod 21, 28 is fastened a respective auxiliarycontrol member 33, 34 located in such a manner that a pedal 30, hingedto bearing blocks 3|, 32 is prevented from being operated or pressed ina downward direction.

Springs 35, 36 located on said slide rods between the bearing blocks andthe auxiliary control members serve to locate the latter underneath saidpedal when the same is not being used.

Extension 31 of pedal carries a spring 38, to retain the pedal in anormal .or inoperative position.

When pedal 30 is pressed down, extension 3! will raise valve member 39for the release of air pressure to lower the head l2.

After said valve member has been raised it will be prevented fromassuming its original position 15 through a pawl 40 hinged to frame I0,engaging an extension 4| of valve member 39.

Lever42 forming a part at pawl 40 is normally located underneath thehead of valve member 43 of valve I l.

A push rod 44 slidably mounted to frame l0 resting on a push lever 45and forming a part v with lever 42 and pawl 40, serves to release thelatter from valve member 39 and thereby eliminate the air pressure onpiston l8 and head l2. 2 Pushrod 44 also serves to operate valve I! tocause piston l8 to remove head l2 from buck l l to a position asindicated in dotted lines.

The operation of the safety control as illustrated in Figs. 1, 2, and 3consists in the depression of operating levers 2|, 22 by both hands ofthe operator, to permit the latter to actuate pedal 30. It is obviousthat the depression of only one of the operating levers will not releasethe pedal, so that in this manner the operator is automatically forcedto keep her hands away from the buck while the head of the press isdescending. When pedal 30 is depressed and valve I6 is caused to permitair pressure to lower head l2 as shown in Fig. 2, the pressure willremain on buck l l until the operator desires the same to be released.This is done by means of pushrod 44, the function of which has alreadybeen described. 45

In the modification of Figs. 4 and 5 pedal 30 has been eliminated and afoot operated valve Ilia is located underneath two auxiliary controlmembers 53, 54 fastened to respective sliderods 51, 58 which are locatedby respective springs 55, 56. These control members, which overlap eachother, are moved to left and right in the manner described, hereinabovefor the other construction, and will not permit the operator to depressthe valve unless both of her hands have removed the control members toenable her to place her foot between the same, and then cause themachine to operate. If it is desired to keep both head 2| and platform20, in a raised position while the machine is idle, the air pressure inpipe l9 may be shut off through stopcock 29.

I claim:

'1. In a pressing machine, coacting press elements therein, fluidpressure means to actuate said press elements, a valve mechanism tocontrol said fluid pressure means to actuate said press; auxiliarymembers for obstructing the actuating of said valve mechanism and meansrequiring the use of both hands for moving said auxiliary obstructingmembers to permit said valve mechanism to be actuated for controllingthe fluid'power to effect the closing of said pressing elements,retaining means for holding said valve actuated to keep said presselements in the position after said valve had been actuated, andseparate manually operated means for releasing retaining means to allowsaid pressure means and valve to separate said coacting elements.

2. A press comprising a stationary buck, a movable head, fluid powermeans for opening and closing the head on the buck, control valves forsaid power means, a pedal operated mechanism for actuating one of saidcontrol valves, a pair of auxiliary control members normally obstructingaccess to said pedal adapted to be actuated by both hands to permitaccess to said pedal, to control said, valve, for admitting fluid tosaid fluid powermeans to efiect the closing of the head on the buck, andseparate valve controlling means to control the fluid power means toeffect the opening of the head from the buck.

3. In a pressing machine, coacting press elements, fluid pressure meansto effect pressure between said press elements, a pedal to control theflow of fluid to said fluid pressure means, auxiliary members forpreventing the actuation of said pedal, and control means requiring useof both hands for rendering said auxiliary members inefiective toprevent the actuation of said pedal to permit said pedal to be actuated,means for maintaining the flow of fluid pressure to said fluid pressuremeans after said pedal had been actuated, and means independent of thetwo hand control means for controlling the said fluid 10 pressure meansto cause the same to separate said press elements.

4. In a pressing machine, coacting press elements, fluid pressure meansto effect pressure between said press elements, a pedal to control theflow of fluid to said fluid pressure means, auxiliary members forpreventing the actuation of said pedal, and control means requiring useof both hands for rendering said auxiliary members ineffect ve toprevent the actuation of said pedal to permit said pedal to be actuated,and means independent of the two hand control means for controlling thesaid fluid pressure means to cause the same to separate said presselements.

5. In a pressing machine, coacting press elements, fluid power means foreffecting pressure between and for separating said elements, a pedal, avalve operated by said pedal for admitting fluid to said power means tocause said pressing elements to effect pressure therebetween, barriermeans to inhibit access to said pedal, a pair of auxiliary controlmembers adapted to be actuated by both hands to remove said barriermeans to allow access to said pedal to permit actuation thereof, andseparate valve means for 5 controlling said power means to separate saidpress elements.

LEO M. KAHN.

